The estrogen hormones, estrone and estradiol, are involved in many physiological processes. The formation of these steroids is regulated by a number of enzymes. The enzyme aromatase is the rate limiting enzyme in the non-reversible conversion of the androgen hormones, testosterone and androstenedione, to the estrogen hormones, estradiol and estrone. Compounds such as aromatase inhibitors may thus regulate or inhibit androgen to estrogen conversion, and have therapeutic utility in treating clinical conditions potentiated by the presence of estrogens.
19-Nordeoxycorticosterone (19-norDOC) is known to induce mineralocorticoid hypertension. In the biosynthetic formation of 19-norsteroids, such as 19-norDOC, the initial step is the adrenal hydroxylation of an appropriate steroid such as deoxycorticosterone (DOC). The inhibition of the biosynthetic formation of 19-norDOC by inhibition of 19-hydroxylation of DOC would thus serve to decrease the level of 19-norDOC present in the animal involved and reduce hypertensive effects attributable to the presence of this material.